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Winterizing a closed cooling system

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Repsolboy1

New member
Hi,
I bought this boat this year with a 2004 Mercruiser 350 mag mpi horizon package and a Bravo 2 out drive. On previous boats, I normally ran anti freeze through the outdrive but this boat has a 'coolant' and a hull thru raw water pick up hose with a lever. When winterizing, will it be enough if I put ear muffs to the out drive and run the engine or should i use the hull thru pick up hose for anti freeze?
 
you use the one that is connected to the raw water pump . just as easy to drain the raw water side of the heat exchanger and risers(manifolds) if raw water cooled . if you decide to fog the motor it should be done with a remote tank with the winterizing mix.
 
Repsolboy1 said:
Hi,
I bought this boat this year with a 2004 Mercruiser 350 mag mpi horizon package and a Bravo 2 out drive. On previous boats, I normally ran anti freeze through the outdrive but this boat has a 'coolant' and a hull thru raw water pick up hose with a lever.
When winterizing, will it be enough if I put ear muffs to the out drive and run the engine or should i use the hull thru pick up hose for anti freeze?
Click to expand...

As per your first photo, it looks as though your seawater path up and through the drive has been completely circumvented in lieu of a thru-hull water pick-up.
If so, trying to run AF in through the garden hose muffs will not work.



Bt Doctur said:
1..... you use the one that is connected to the raw water pump . just as easy to drain the raw water side of the heat exchanger and risers(manifolds) if raw water cooled .

2.....if you decide to fog the motor it should be done with a remote tank with the winterizing mix.
Click to expand...


1..... Agree!


2..... I don't believe that this method is actually considered to be "fogging".
Fogging (via the conventional method) will harm FI systems (air sensing circuits) and is typically performed on carbureted engines only.

Instead, you'll be running an oil enriched fuel mixture through the FI system by removing the main/primary fuel filter cartridge and by adding your oil enrichment directly into the cartridge.
This will be followed by operating the engine for a given amount of time until the mixture reaches and enters the FI system.

You can certainly do what Bt Doc suggests, but I don't believe that it's necessary when the main/primary fuel filter cartridge can be used.

Bt Doc, what say yee?



.
 
They do make a flush attachment for thru-hull cooling intakes. It looks like a toilet plunger with a hose connection. You could introduce antifreeze thru one of those.
 
why bother to remove the filter/sep unless your changing it. I use a 1 gal tank with 91 octane, marvel mystery oil, 2 stroke oil, and sta-bil.
most of my customers are equipped with an additional shutoff valve at the sep and a additional one on the main inlet from the tank.
shut off the main, open the remote, connect the hose or use a quick connect, and run the engine.
 
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why bother to remove the filter/sep unless your changing it. I use a 1 gal tank with 91 octane, marvel mystery oil, 2 stroke oil, and sta-bil.
most of my customers are equipped with an additional shutoff valve at the sep and a additional one on the main inlet from the tank.
shut off the main, open the remote, connect the hose or use a quick connect, and run the engine.
Click to expand...

Don't get me wrong.... I fully understand your points.
However, please consider my counter-points:

If the fuel filter cartridge will be changed as part of the winterizing procedure anyway (as it should be), and if the filter base is not set up for the valving and additional hose, why bother to do all of that?

If the cartridge is not being changed at this time, it's very easy to remove it and dump the contents, and then fill it up with marvel mystery oil, 2 stroke oil and sta-bil enriched mixture.

Either way, the old or new fuel filter cartridge becomes filled with the oil enriched mixture....... of which will be pushed into the FI system when the engine is fired up.


A filter cartridge of this mixture is more than enough to do the job!



.
 
Thank you all for the help. Rather than starting up and trying to figure out where to hook up the anti freeze from, can i pump air into the system, remove these 4 blue drain plugs and make sure that the water drains out ? There is one on heat exchanger, 2 near water pump on starboard side and one in front of the engine. Just want to make sure that I did not miss any more drain plugs .


In a closed cooling system such as this, does the raw water still circulate through the engine block and runs the risk of cracking a block ?
 
Check your owner's manual for the number and location of the drain plugs...they should be clearly identified as to raw water or coolant....and best to 'poke' into the hole to make sure any debris doesn't inhibit the water draining out.

in a 'closed system', only the coolant mixture flows thru the block.

Another option for the belt driven pump is to remove the hose from the seacock introduce the "pink stuff" thru it....we use a 5 gallon bucket with a hose barb on the bottom and a 5' length of 1.25" ID hose....a plastic hose barb with the barbs filed down will join the two hoses (with clamps).
 
On my FWC 5.7, the blue plugs drain the "freshwater" side of the engine. I have a "T" fitting and a hose valve permantly plumbed in (See pix) and winterize the cooling system by hooking up a 3 to 4 ft section of garden hose with the suction end in a 5 gal pail. I dump 3 gallons of antifreeze in the bucket and start the engine and shut it off before the bucket runs dry. Remainder of anti freeze gets dumped into the bilge. Experience has shown me ( on my rig) that a good flow of anti freeze out the exhaust ( thru transom w/mufflers) starts at just over 2 gallons in the
system. Neither the valve (brass) nor the 1 1/4 to valve reducer (galvanized) are "marine", so they get replaced every 3 or 4 seasons. The type of valve I used is usually sold as a "boiler drain valve" and is threaded directly into the reducer. The same "port" is used to flush my system with freshwater during the season except I run the engine with the dockside hose running in the bucket. Fill bucket at least halfway before starting engine and keep a sharp eye on the water level. Sometimes dockside flow won't keep up with the engine's raw water demand.
ThruHull_rawwaterinlet_internal_2266.jpg
 
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Thank you for the help everyone. I finally did it this weekend and got stumped by a couple of things.

1) When I used the single point drain air actuator system and filled the system with air, the engine coughed up about a glass of water from the outlet in the front of the engine. That's about it. Then I opened the blue drain plugs, but no water came out. I poked and made sure there is no debris blocking the holes. In previous engines, lot of water came out and not sure if the closed cooling system engines retain much raw water. How much water is expected to drain out from a closed cooling system ?

2) Once the water is drained, I put on muffs to the out drive with antifreeze and also removed the through hull water pick up and placed it in a bucket of anti freeze. Both water intakes did not 'suck in' any anti freeze, once the engine was started. After 20 seconds or so, I had to "pour" the anti freeze into the through hull pick up hose and verified that it came out of the exhaust.
 
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Repsolboy1 said:
Thank you for the help everyone. I finally did it this weekend and got stumped by a couple of things.

1) When I used the single point drain air actuator system and filled the system with air, the engine coughed up about a glass of water from the outlet in the front of the engine. That's about it. Then I opened the blue drain plugs, but no water came out. I poked and made sure there is no debris blocking the holes. In previous engines, lot of water came out and not sure if the closed cooling system engines retain much raw water. How much water is expected to drain out from a closed cooling system ?
Even while your engine is fitted with a Closed Cooling System, be very careful with the single point drain systems.


2) Once the water is drained, I put on muffs to the out drive with antifreeze and also removed the through hull water pick up and placed it in a bucket of anti freeze. Both water intakes did not 'suck in' any anti freeze, once the engine was started. After 20 seconds or so, I had to "pour" the anti freeze into the through hull pick up hose and verified that it came out of the exhaust.

While this pertains more so to raw water cooled engines, I believe that some points are worth reading. http://www.amazon.com/review/R3BD7X6QC3KCFR/ref=cm_cr_pr_viewpnt#R3BD7X6QC3KCFR

Maybe you have friends with RWC engines who may be tempted to use these kits.
Click to expand...
 
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makomark said:
Check your owner's manual for the number and location of the drain plugs...they should be clearly identified as to raw water or coolant....and best to 'poke' into the hole to make sure any debris doesn't inhibit the water draining out.

in a 'closed system', only the coolant mixture flows thru the block.

Another option for the belt driven pump is to remove the hose from the seacock introduce the "pink stuff" thru it....we use a 5 gallon bucket with a hose barb on the bottom and a 5' length of 1.25" ID hose....a plastic hose barb with the barbs filed down will join the two hoses (with clamps).
Click to expand...
 
I was looking in the service manual so will look in the owners manual
I don’t believe this set up has a seacock as the raw water comes in via the leg
 
So you suggest removing the intake hose on the raw water pump and put a hose on it from the antifreeze bucket then run the motor ?
 
Yoeman said:
So you suggest removing the intake hose on the raw water pump and put a hose on it from the antifreeze bucket then run the motor ?
Click to expand...
Yes, that's what is suggested. On your closed cooling system, the block should already be full of anti freeze. The things that are vulnerable to freeze damage are the raw water pump and the heat exchanger, along with any fluid coolers that are in line with the raw water pathway. The manifolds should be drained via the blue plugs.
 
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